Dr. Schechter will obtain observations of Cepheid variable stars and carbon stars to determine the shape of the potential of our Galaxy. In both cases photometry will yield distances to the stars while spectroscopy will yield velocities. The data from the Cepheids will also be used to determine the distance from the Sun to the center of our Galaxy. It has proven difficult to determine the relative contributions of a disk, a bulge, and dark matter to the total masses of galaxies. A better understanding of the relative importance of dark and luminous matter in a galaxy is a prerequisite to understanding how galaxies form and evolve. In the Milky Way galaxy one can measure all three components of position and velocity for specific tracers of mass. Our knowledge of the mass distribution in our Galaxy can then be applied to understanding the structure of other galaxies. Dr. Schechter's research addresses two of the fundamental problems in galactic structure -- the degree to which orbits are non- circular at the distance of the Sun in our Galaxy and the distance of the Sun to the center of our Galaxy.
